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Re: Telomerase is an enzyme that is produced only in cells that are active
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04 Dec 2017, 07:16

Hi,

I went with C through negation technique. As per powerscore, the correct choice cannot be negated based on the stimulus.

If we negate option C, we get "the presence of telomerase in bone tissue is indication of bone marrow cancer" which is clearly opposite of what the stimulus states. Since the opposite statement is false, this option c must be correct.

Could someone please confirm if this approach is fine?

Also, can any expert confirm if this option can be arrived at through conditional reasoning?

Re: Telomerase is an enzyme that is produced only in cells that are active
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21 May 2018, 08:03

MartyMurray wrote:

freetheking wrote:

Telomerase is an enzyme that is produced only in cells that are actively dividing. For this reason it is generally absent from body tissues in adults. Bone marrow is an exception to this rule, however, since even in adults, bone marrow cells continually divide to replace old blood cells. Cancers are another exception, because their cells are rapidly dividing.

The information provided most strongly supports which of the following?

A. Telomerase is the only enzyme that is present in cancerous cells but absent from cells that are not actively dividing.B. In children, the only body tissues from which telomerase is absent are those in which cells are not rapidly dividing.C. The presence of telomerase in bone marrow is no indication of bone marrow cancer.D. Cancer of the bone marrow develops more rapidly than cancer growing in any other kind of adult tissue.E. The level of telomerase production is always higher in cancerous tissue than in noncancerous tissue

OA lateR~

This question has been giving many people a lot of trouble, and the truth is that the reason there are so many doubts is that the question has issues, as some of the wording does not quite clearly state what the question's creator felt that it states. So let's define what the issues are.

First let's define what they are not. Answer choices A, D and E, are fine. Each of them says something that clearly cannot be inferred from what the prompt says.

A does not have to be true. There could be all manner of differences between cancerous cells and cells that are not actively dividing.

D cannot be inferred, as what the prompt say about bone marrow does not clearly indicate anything about the rate at which bone marrow cancer grows.

E cannot be inferred as the prompt does not indirectly or directly support any conclusions about relative levels of telomerase production. It merely provides a binary set of situations, cells in which telomerase is produced and cells in which telomerase is not produced.

Ok so, with A, D, and E out, we are left with the two problematic answer choices.

First let's talk about B, "In children, the only body tissues from which telomerase is absent are those in which cells are not rapidly dividing."

Since C is the OA, the creator of this question clearly felt that B cannot be inferred from the prompt, and here is the logic underlying that stance.

For all we know, while the prompt says that telomerase is only produced by cells that are dividing, it is possible that not all cells that are dividing produce telomerase. That cells that are dividing may not produce telomerase seems possible, and this logic means that B cannot be inferred.

However, there are aspects of the wording of the prompt that could be taken to indicate that actually all dividing cells produce telomerase.

The prompt says, "Bone marrow is an exception to this rule, however, since even in adults, bone marrow cells continually divide to replace old blood cells." The prompt also says, "Cancers are another exception, because their cells are rapidly dividing."

The implication that one could take from those statements is that SINCE BONE MARROW CELLS AND CANCER CELLS DIVIDE, THEY ARE EXCEPTIONS. The prompt does not say that since they divide they CAN BE exceptions. It say that since they divide they ARE exceptions, which can be taken to mean "SINCE THEY DIVIDE, THEY PRODUCE TELOMERASE."

That somewhat reasonable interpretation of the meanings of the sentences in the prompt could in turn be taken as implying that CELLS THAT DIVIDE PRODUCE TELOMERASE, which supports B.

I believe that that analysis partially explains why B is being chosen by so many people.

Now let's look at C, "The presence of telomerase in bone marrow is no indication of bone marrow cancer."

The issue in C is similar to the issue in B, actually.

Just as B does not say CAN BE AN EXCEPTION, C does not say, IS NOT NECESSARILY AN INDICATION.

C says that telomerase in bone marrow is NO indication of cancer. That's an extreme statement, as telomerase in bone marrow could be coming from cancerous cells. I realize that I am playing with subtle differences, but I think that if C were worded even "The presence of telomerase in bone marrow is NOT AN indication of bone marrow cancer," C would be slightly clearer.

So if the wording in the prompt regarding the bone marrow and cancer exceptions were just slightly clearer, and if a couple of words in C were changed in order to increase clarity, this question would perhaps go from 700 level to 600 level.

Re: Telomerase is an enzyme that is produced only in cells that are active
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13 Jun 2018, 04:47

It took too much time, because I could not choose between C and B. C is wrong. I could not eliminate C because I was making an assumption - that cells of children are actively dividing.

That body cells of adults do not actively divide, does not mean that body cells of children actively divide. No evidence for this. I also made an assumption that people can be either adult or children.

Re: Telomerase is an enzyme that is produced only in cells that are active
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09 Sep 2018, 07:59

Well, we already have OA and great explanations; however I just wanted to add why I missed this question and how I made the mistake. May be it will be helpful for others too:

Mistake Analysis:

Initially I was inclined towards E but rejected and chose B. Looking at facts in the premises and since its inference question, we can always eliminate B (contains ONLY) and E (contains ALWAYS). Also, the argument does not mention about children so we can’t confirm B and also does not talk anything about level of telomerase, so E can be eliminated straight away.

Why I got confused with E>> because it talked about canc Vs non-canc and it was given in premise that canc cells are rapidly dividing but a more careful reading would have revealed the word LEVEL because level is not given in premises.

Why got confused with B>> It matched with the info given in premises that Telomerase is produced only in cells that are dividing and is absent in adult tissues so I concluded that in children the only tissues it will be absent are the ones that are not dividing. BUT this conclusion cannot be verified BECAUSE we are not given any info in premises to match about children's tissues or cells.
_________________

Retaking gmat for second time, any re-takers please feel free to connect.

Re: Telomerase is an enzyme that is produced only in cells that are active
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18 Dec 2018, 09:32

Bone marrow is an exception to this rule, however, since even in adults, bone marrow cells continually divide to replace old blood cells.and Cancers are another exception, because their cells are rapidly dividing.

are mutually independent hence C is the answer.

gmatclubot

Re: Telomerase is an enzyme that is produced only in cells that are active &nbs
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18 Dec 2018, 09:32